interrogate barfs on platform-sdk dir, hack around by filtering out that dir

dtool/Config.Win32.pp

@@ -6,8 +6,6 @@
 // compiler features, etc.
 //
 
-// -D__stdcall seems dangerous, interrogate will assume c-calling convention for WINAPI fns
-
 // What additional flags should we pass to interrogate?
 #define SYSTEM_IGATE_FLAGS -longlong __int64 -D_X86_ -DWIN32_VC -D"_declspec(param)=" -D_near  -D_far -D__near  -D__far